From the book : Evolutionary Psychology 10 issue 1 : 120-135. Because women‟s faces and bodies carry different cues of reproductive value, men may attend to different perceptual cues as functions of their long-term versus short-term mating motivations. We tested this hypothesis in three experiments on 135 male and 132 female participants. When influenced by short-term rather than long-term mating motivations, men‟s attention was captured by (Study 1), was shifted to (Study 2), and was distracted by (Study 3) the waist/hip area rather than the face on photographs of attractive women. Similar effects were not found among the female participants in response to photographs of attractive men. These results support the evolutionary view that, similar to the attentional selectivity found in other domains of life, male perceptual attention has evolved to selectively capture and hold reproductive information about the opposite sex as a function of short-term versus long-term mating goals.
Paternité, pas d'utilisation commerciale, partage des conditions initiales à l'identique
Langue
English
Extrait
Evolutionary Psychology
www.epjournal.net–2012. 10(1): 120135
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Original Article
Automatic Attention towards Motivation
Face
or Body as a Function of
Mating
Hui Jing Lu, Department of Educational Psychology, The Chinese University of Hong Kong, Hong Kong SAR, China.
Lei Chang, Department of Educational Psychology, The Chinese Universi ty of Hong Kong, Hong Kong SAR, China. Email:du.hk@guckhe.liehcna(Corresponding author).
Abstract: Becausewomen’s faces and bodies carry different cues of reproductive value, men may attend to different perceptual cues as functions of their longtermversus short term mating motivations. We tested this hypothesis in three experiments on 135 male and 132 female participants. When influenced by shortterm rather than longterm mating motivations, men’s attentionwas captured by (Study 1), was shifted to (Study 2), and was distracted by (Study 3) the waist/hip area rather than the face on photographs of attractive women. Similar effects were not found among the female participants in response to photographs of attractive men. These results support the evolutionary view that, similar to the attentional selectivity found in other domains of life, male perceptual attention has evolved to selectively capture and hold reproductive information about the opposite sex as a function of shorttermversuslongterm mating goals.
Keywords: automatic attention, longterm mating, shortterm mating, face, body
The human cognitive system has evolved to efficiently solve fitnessrelevant problems. From relatively automatic processes, such as attention and memory, to more effortful processes, such as logical reasoning and decisionmaking, psychological adaptations are present at all levels of human cognition (Maner, Gailliot and DeWall, 2007). In processing mating information, for example, one must first identify and differentiate between features of the opposite sex carrying different implications for reproduction. After reproductivediagnostic cues have been perceived, one must decide on functionally beneficial behavioral responses that effectively facilitate reproductive success. A recent study reported that men preferred to look ata woman’s face when primed by long term mating goals, whereas they preferred to look ata woman’s body when primed by
Attention towards face or body
shortterm mating goals (Confer, Perilloux and Buss, 2010). These findings point to a matingspecific adaptive functioning of the higher order cognitive process. Does the lower order cognitive system have a similar perceptual preference between the face and body which is driven by long termversus reproductive goals? The purpose of the shortterm present study is to answer this question by assessing automatic attention to the face or the body of the opposite sex under longterm or shortterm mating motivation.Attention is the first step in encoding information. Its evolutionary function is to search for and capture information relevant to survival and reproductive goals. Given limited or finite attentional capacity (resulting from life history tradeoffs and the evolutionary principle of economy) and the diverse and complex social information potentially available, attentional selectivity has evolved to capture and hold information that is most relevant to fitnessenhancing goals. For example, human attention, as well as that of other animal species, is preferentially drawn to animate over inanimate objects in order to avoid predation (New, Cosmides and Tooby, 2007), and it is more sensitive to emotional rather than nonemotional facial expressions of conspecifics as a means for conducting social interactions more effectively (Fox, Russo, Bowles and Dutton, 2001). Thus, limited attentional capacity should be used in the most necessary fashion, thereby providing optimal information for subsequent cognitive processing. Attentional selectivity is equally important in processing mating information. In a mating context, a heterosexual individual must be able to differentiate members of the opposite sex of highversuslow mate value (Maner, Gailliot and DeWall, 2007). Automatic attention to features representing different aspects of mate quality is essential for efficient identification and differentiation of suitable potential mates. Human attention is able to target (Duncan, Park, Faulkner, Schaller, Neuberg and Kenrick, 2007) and fixate toward (Maner, Gailliot and DeWall, 2007; Maner, Gailliot, Rouby and Miller, 2007) features of highquality mating partners. For example, Duncan et al. (2007) asked participants to detect changes in an array of four oppositesex faces that differed in their level of attractiveness and appeared and disappeared alternately. Male participants with unrestricted sociosexual orientation were faster at detecting changes in attractive female faces than they were at detecting changes in unattractive female faces, suggesting attentional selectivity and acuity over the facial features that signal high mate quality. Similar to such attentional engagement is the effect of sexual attractiveness on attentional disengagement, whereby male participants took a longer time to disengage their attention from attractive female faces than they did from unattractive ones (Maner et al., 2007). Automatic attention to mate quality also differed between participants who either were primed by longterm romantic relationships (Maner, Rouby and Gonzaga, 2008) or were committed to longterm relationships (Maner, Gailliot and Miller, 2009) and those who were not primed to be or were not already in a committed relationship. Similar effects were not found among women. Whereas the above supports attentional selectivity towards aspects of mate quality distributed across different potential mates, selective attention is also exercised over different facial and bodily features of the same individual. This may be particularly true for human males who face the challenge of assessing two matingrelated uncertainties within the same individual: (1) uncertainty over female fertility (i.e., actual reproduction),
including fecundity (i.e., reproductive potential) which is age graded (from menarche to menopause), and fertilizability, which is time sensitive (the fertile phase is brief and concealed during the ovulation cycle), and (2) uncertainty over his own paternity because males face the challenge of female infidelity which is facilitated by some of the same female fertility characteristics (e.g., concealed ovulation) . The female face and body provide both overlapping and distinct assessment information for the male evaluator. The face is the best indicator of age , which represents perhaps the most important aspect of a female’smate value (Thornhill and Gangestad, 1999). The color, luster, and volume of hair indicate youth and health (Gangestad and Scheyd, 2005), whereas the overall facial impression of femininity implies fertility (Enlow, 1990) and maternal nurturing and warmth (Perrett et al., 1998). Corneocytes and collagen, which give the skin the appearance of softness and vascularization, are enhanced by estrogens and these degenerate after menopause (Farage, Neill and MacLean, 2009). The face also contains information about fluctuating asymmetry and smoothness of skin which, as indicators of overall immunity (Sugiyama, 2004), represent longterm mating and child rearing considerations. Finally, facial features and expressions contain perceptual cues to the assessment of paternity uncertainty. A face may look honest or dishonest, and sexually reserved or flirtatious (Grammer, Honda, Juette and Schmitt, 1999; Schmidt and Cohn, 2001), whereas such assessments cannot be made from visual inspections of the body. The major contributors to female bodily attractiveness include waisttohip ratio (Singh, Dixson, Jessop, Morgan and Dixson, 2010) and body mass index (Cornelissen, Hancock, Kiviniemi, George and Tovée, 2009), both of which indicate her current fertility status (Confer et al., 2010). Optimal reproductive potential is reached at around 17 years of age and fertility rate peaks at around 24 years of age (Buss, 1994; Symons, 1979). These hormonebased developmental characteristics are arguably best summarized by the waist tohip ratio. Thus, calibration of overall reproductive value or fecundity as mostly indicated by the face is futureoriented, whereas fertilizability, most noticeably advertised by the waisttohip ratio, carries time immediacy. For example, current infertility of a pregnant woman is best shown by her unattractive waisttohip ratio, whereas her facial features representing overall reproductive value (including future fertility) would not show similarly drastic changes. On the other hand, pregnancy as indicated by a large waisttohip ratio represents a current state of infertility, whereas honest, prudent, and sexually reserved facial cues and expressions are useful for assessing future fidelity that is related to paternity. As an adaptation to these potentially inconsistent cues, especially in representing futureversus current reproduction, male visual attention may have evolved to selectively attend to different cues for longtermversusshortterm mating goals. In the present study, we tested the hypothesis that men’s visual attention would automatically shift to the face or body of the opposite sex as a function of longtermversusshortterm mating motivation. We focused this hypothesis on men because, as an adaptation to concealed and premenopausal ovulation, men have evolved special visual sensitivity toward secondary sexual features distributed in the female face and body (Thornhill and Grammer, 1999). We included women as a comparison group, in whom the same perceptual effects were not expected, because women do not have the same fertility and maternity challenges. We also controlled for sociosexuality which taps individual
differences in one’sinterest and willingness to engage in casual sexual relationships (Penke and Asendorpf, 2008) and has been found to influence aspects of mating behavior (e.g., Maner et al., 2007) including visual attention (Duncan et al., 2007). We tested our hypothesis in three experiments by using attention disengagement, engagement, and distraction paradigms after participants were primed with longtermversus shortterm relationship goals. In Study 1, we used a dot probe task to examine the speed with which the participants disengaged their attention from the face or the body of the opposite sex. In Study 2, we examined how long the participants engaged their attention towards the face or the body of the opposite sex while they were performing a change detection task. In Study 3, we examined the probability of, and the speed with which participants were distracted by the face or body while they were simultaneously performing another visual task. We expected that, among men but not women, attention would be more drawn to and fixed on the face of the opposite sex when primed by the longterm mating goal, and relatively more drawn to the body under the shortterm mating goal.
Study 1
Methods
Participants One hundred and eleven heterosexual undergraduate students (mean age = 20.61, SD = .87, 47 males) were recruited from a 3year community college in a large city in southern China. By random assignment, 56 participants were primed for a longterm relationship and the others were primed for a shortterm relationship. The dependent variable was derived from a task in which the participants had to view photographs of attractive members of the opposite sex. Priming Material For three minutes, the participants read one of two scenarios of similar length about a longterm or a shortterm mating relationship in which the participants were asked to imagine themselves as the protagonist of the mating scenario. This method has been successfully used to activate longterm or shortterm mating goals (e.g., Griskevicius, Cialdini and Kenrick, 2006). In the longterm scenario, a male participant was asked to imagine that he spent a wonderful evening with his attractive girlfriend, cooking and having dinner at his place, talking about how he would like to spend the rest of his life with her and to provide her and their children with a nice home and a comfortable living, and, at the end of the evening, he walked her home, kissed her goodnight and went back home by himself. In the shortterm relationship scenario, a male participant was asked to imagine that, during an overseas trip, he met and flirted with an attractive woman in a bar, and the woman liked him. They then went to his hotel room and had a passionate night, and on the next day he said goodbye to her and continued with his trip. The two priming stories for the female participants were similar to those for males with the exception that the protagonist was a woman who either planned her future life with her boyfriend (longterm condition) or had a passionate night with a handsome man (shortterm condition).
Figure 1.Illustration of the attention task in Study 1. The example shows stimuli used for male participants, whereas female participants used a different set of stimuli using male targets.
Attention Disengagement TaskThe“Dot Probe Task” has been used previously to measure participants’ focus of attention and to assess biases of attentional disengagement away from specific stimuli (e.g., Maner, Gailliot and DeWall, 2007). If a participant was attracted to the face (or the body) shown in the oppositesex photograph, then his or her attention would be fixed to that part. This fixation should therefore attenuate his or her attention away from the new stimulus, if that stimulus is presented in a position different from the original stimulus, resulting in a slower response in this condition. In each trial, in the center of the computer screen, a fixation cross“+”appeared for 500 ms, and then an oppositesex photograph appeared for 500 ms (Figure 1). The photograph showed the person from head to knees and was positioned so that the chest area appeared in the center of the screen with the face and the waist each at a similar distance from the center. Immediately after the photograph appeared, an object (a circle or a square) appeared either in the upper (the face position in the previous photograph) or the lower part of the screen (the waist position in the previous photograph). The participant’s task was to identify as quickly as possible whether the object was a circle or a square; to do this they had to pressthe letter “O”or“P”on the keyboard. After each response, the participant was given a 1,000 ms break before the next trial. There were four practice and 40 test trials. In
half of the trials, t he object appeared on the up per part of the screen and, in the other half, the object appeared on the lower part of the screen . Half of the objects were circles and half were squares. The order of location and shape of the object w as randomized. The photographs (44 women or 44 men for participants of the opposite sex ) were selected from internet picture ba nks and were processed by Photoshop in order to achieve the same size and a similar brightness and contrast. Rated by an independent group of 20 undergraduate male and 18 female stud ents on a 10 point scale, the attractiveness rating s wereM 7.62 = (SD= .46) for the female photographs andM= 7.48 (SD= .66) for the male photographs. Sociosexual OrientationWe used scores on the Revised Sociosexual Orientation Inventory (Penke and Asendorpf, 2008)as a covariate to control for individual differences in participants’ attitudes toward casual sex. Sample items include“with how many different partners have you had sex within the past 12 months”and“Ican imagine myself being comfortable and enjoying‘casual’sex with different partners.”Rated on a uniform 9point scale, higher SOI scores indicate more unrestricted sociosexual orientation or higher willingness to engage in an uncommitted sexual relationship. The internal consistency reliability estimate in this study wasα= .71. Procedure and Design All tasks were completed individually. Upon arriving at the experiment room, each participant signed a consent form and received a brief introduction about the experimental processes. The participant was then given the mating scenario which they were asked to read and to remember the details for a memory test later on. Afterwards, the participant completed the attention task by viewing 44 oppositesex photographs. The participants completed the Sociosexual Orientation Inventory last. The design was a 2 (participant gender) × 2 (mating prime: longtermversusshortterm, manipulated between participants) × 2 (focus of attention: faceversus body, manipulated within participants) mixed model ANCOVA, with SOI score as a covariate.
Results
Trials with incorrect responses (3.10%) and those with unreasonably fast responses (usually due to starting the task before the starting prompt; RT < 300 ms; .85%) were excluded from the analysis. Following previous priming experiments (e.g., Lemm, Dabady and Banaji, 2005), extremely long responses (more than 3 SD above the mean of each participant) were trimmed to the RT value of 3 SD above the mean (.74%). If a participant’s attention was previously attracted to the face, his or her response to the object appearing in the face position should be faster than that appearing on the waist/hip position. Similarly, if the participant’s attention was previously drawn to the waist/hip position, his or her response to the object appearing on the face should be slower than that appearing on the waist/hip position. The ANCOVA showed a main effect ofparticipantgender, reflecting generally
2 slower responses from females compared to males (F(1, 106) = 6.17,p= .015,η= .06). There was also a twoway interaction betweenmating prime andfocus of attention (F (1, 2 106) = 4.46,p= .037,η= .04), and a threeway interaction betweenmating prime,focus of 2 attentionandparticipant gender(F(1, 106) = 10.18,p= .002,η= .09, Figure 2). Separate analyses of the male participants showed an interaction effect between the 2 mating primeand thefocus of attention(F(1, 44) = 14.64,p< .001,η= .25), but no main 2 effect ofmating prime(F(1, 44) = .16,p= .69,η= .004) orfocus of attention(F(1, 44) = 2 .21,p= .65,η .005). The male participants primed with shortterm mating goals = responded to the object located in the waist/hip position(M 483.25 ms, =SD = 77.64) 2 faster than in the face position (M= 504.17 ms,SD= 80.85;F(1, 21) = 7.06,p= .015,η= .25), thereby suggesting that their attention was previously fixed at the waist/hip position. By contrast, when primed with longterm mating goals, there were no significant differences in men’s response time between the waist/hip position (M 487.56 ms, =SD = 2 54.84) and the face position (M = 478.28 ms,SD 53.45; =F 22) = 1.03, (1,p= .32,η = .04). For the female participants, there was no main effect either formating prime (F (1, 2 2 61) =.49,p= .48,η .008) or for =focus of attention (F (1, 61) = .02,p= .88,η .00). = There was also no interaction betweenmating primeandfocus of attention(F(1, 61) = .63, 2 p= .43,η .01). =next study, we used the “change blindness paradigm” to furtherIn the assethe location of the participants’ natural visual attentionss (Rensink, O’Regan and Clark, 1997).
Figure 2.Attentional disengagement from bodies and faces of the opposite sex as functions ofmat
Study 2
Method
Participants and Design One hundred and sixteen heterosexual students (mean age = 20.62,SD = 1.02, 44 males) were recruited from a community college in a metropolis of southern China. They were randomly assigned to either a longterm (n = 58) or shortterm relationship priming conditions. We used a 2 (participant gender) × 2 (priming of mating motivation: long versus × 2 ( shortterm)focus of attention: faceversus body) mixed model design. The dependent variable was the participants’ reaction time in performing a change blindness task. Preference of AttentionThe“change blindness paradigm”, which has been successfully used to access preferential attention to specific objects (New, Cosmides and Tooby, 2007), was used to measurethe participants’ visual preference for the face or the body. Two pictures that were identical except for one feature change either in the face or in the waist/hip area of the oppositesex photograph were presented to the participants as a stream of rapidly alternating pictures on the computer screen (Figure 3). As shown in Figure 3, the change occurred on the clothes and accessories in the waist/hip area or, for the face position, in the hairstyle and clothing accessories near the face. The faster that a participant spotted the difference between the two flashing alternations, the more preferentially he or she attended to the changing locale. In each trial, a fixation cross“+”of 500 milliseconds was followed Evolutionary Psychology–ISSN 14747049–Volume 10(1). 2012. 127
Attention towards face or body
by a flash of two almost identical pictures rapidly alternating on the computer screen. The participants were asked to locate the change by pressingthe “1” keyand then to type a few words to describe the change. Participants then had to click a button at the bottom of the screen to start the next trial. There were four practice trials and 40 test trials. In half of the trials the change was in the face, and in the other half the change occurred in the waist/hip area. The same set of photographs used in Study 1 was used to generate the flashes. The time that elapsed after the first picture appeared and before the computer key was pressed was counted as Reaction Time. Figure 3.Illustration of the change blindness paradigm in Study 2. Below is an example of the stimuli used for male participants (female participants used a different set of stimuli depicting male targets)
Results
As in Study 1, extremely long responses (above 3 SD from the mean of each participant) were trimmed to the RT value of 3 SD above the mean (.85%). No responses shorter than 300ms occurred. A 2 (participant gender) × 2 (mating prime: longtermversusshortterm) × 2 (focus of attention: faceversus mixed model ANCOVA with SOI body) score as a covariate showed a main effect ofparticipant gender (F (1, 111) = 40.85,p< 2 2 .001,η .27) and a threeway interaction effect, =F 111) = 17.16, (1,p< .001,η .13 =
(Figure 4). A separate analysis of male participants showed an interaction betweenmating 2 primeandfocus of attention(F(1, 41) = 26.29,p< .001,η= .39), but no main effect of 2 mating prime(F(1, 41) = .07,p= .79,η= .002) orfocus of attention(F(1, 41) = .81,p= 2 .38,η= .02). Males primed with shortterm mating goals detected changes in the waist/hip area(M = 2324.16 ms,SD 576.12) faster than they detected changes in the face ( =M = 2 2535.26 ms,SD 611.40; =F (1, 20) = 5.27,p= .033,η = .21). When primed with long term mating goals, male participants were slower at detecting changes in the waist/hip area (M= 2545.66 ms,SD= 536.59) than they were at detecting changes in the face area of the 2 flashing pictures (M= 2251.67 ms,SD= 486.68;F(1, 20) = 6.75,p= .017,η= .25). For the female participants, there were no significant interactions or main effects. Figure 4.Detecting changes in bodies and faces of the opposite sex as functions ofmating prime
Study 1 used attention disengagement and Study 2 used attention engagement to assess automatic attention to the face or the body. In both studies, a faster response time confirmed our matingrelated hypothesis. In the next study, we used an opposite paradigm to see how much ofan ongoing task was differently distracted by thethe men’s attention to face or the body of attractive members of the opposite sex. Because Study 1 and Study 2 showed no attentional differences between male faces and male bodies among the female participants, the next study used male participants only.
Participants Fortyfour heterosexual male undergraduate students (mean age = 20.72,SD= 1.24) were recruited from a 3year community college in southern China. By random assignment, half of the participants were primed for a longterm relationship and half were primed for a shortterm relationship. The dependent variable was derived from a simple attention task in which participants had to view photographs of attractive members of the opposite sex. Attention Distraction A photograph of an attractive female face or waist/hip area was presented in the centre of the screen. Aletter “O” or “Q” appeared either on the left or the rightside of the face or the waist/hip picture (Figure 5). Each participant’s task was to indentify whether the letter was “O” or “Q”. Response latencyin completing this simple task indicates potential visual distraction from either the face or the waist/hip area.
Design and ProcedureStudy 3 used a 2 (priming ofmating motivation: longtermversus shortterm manipulated between participants) × 2 (distraction of attention: faceversus waist/hip manipulated within participants) mixed design. The procedure was the same as in Study 1 and Study 2 except for the attention distraction task described above. There were four practice trials and 40 test trialsletter “O” or “Q” appeared next to. In half of the trials, the the face picture, and in the other half of trials it appeared next to the waist/hip picture. The position (left or right) and the type of letter (“O”or“Q”) were counterbalanced across the trials.
Results
As before, trials with incorrect responses (3.35%) and unreasonably fast responses